U.S. Pat. No. 4,078,341 to Peterson (hereinafter “Peterson”) discloses a portable building comprised of one or more foldable, prefabricated transverse sections which, when erected and placed end to end, form the side walls and roof of the building. The roof panels in each section are joined with a single pivot on each side and wall sections are joined with a single pivot on each side. Each section can be folded into a stack that is four panels high with the wall panels on the outside of the stack, as previously disclosed in U.S. Pat. No. 3,774,356. Each panel is constructed of a steel channel frame (opening outward) with corrugated metal sheets on each side. Each panel may contain insulation, purlins or gifts, and openings for doors, skylights, windows, and the like. Peterson disclosed U-shaped brackets, welded into the web of channel frames and extending beyond the channel flanges, at predetermined locations, to assist in fastening sections together. Peterson disclosed roof braces and corner braces (roof to wall) made of detachable members with fastener holes in each end, on each side of each section. Front and rear end sections have a reversed channel on the outside end.
U.S. Pat. No. 4,170,852 to Danis, Jr. (hereinafter “Danis”) discloses a folding building that has transverse four-panel sections that stack two panels high, with the wall panels on the underside. Danis also discloses using steel channel frames and corrugated metal sheeting. Danis' stacking allows a ridge brace to be loosely connected to a roof panel and so transported as part of the stack, rather than as a separate piece. Danis also uses a single hinge pin on each side of the roof panel coupling and in the wall couplings.
Folding buildings are portable, in that they can be deconstructed in a reverse process of erecting them, and reassembled in another location.
Demand for folding buildings remain high and the need to improve the economy, reliability, and strength of folding buildings for maintaining a competitive edge remains great. Significant economy can be achieved by improving the speed of erecting the folding building, by improving the safety of crews erecting the buildings, by improving thermal characteristics of the building, increasing the environmental loading and building span and improving stability in shipping, handling and erection.
Therefore, a need exists for improvements to folding buildings to improve the economy, reliability, capacity, and strength of folding buildings.